NEET BIOLOGY

Detailed explanation-1: -Pitfall traps were used to survey populations of invertebrates active at the soil surface (after Luff, 1996) and consisted of 6 cm diameter plastic cups, sunk in the ground with the cup-lip level with the soil surface. Each was two-thirds filled with a 50:50 mixture of tap water and ethylene glycol as a preservative.

Detailed explanation-2: -Dry pitfall trap-A hole in the ground into which a bucket or pipe is placed into the soil so that the mouth is level with the soil surface. These traps are often used to capture small mammals, reptiles and frogs that fall into the pit and cannot escape due to the smooth walls.

Detailed explanation-3: -Pitfall traps usually consist of a beaker that is buried so that the lip of the beaker is level with the ground surface. The trap is then left and the entomologist returns to it at a later date to inspect ‘the catch’. Insects reaching the lip of the beaker slip and fall in and are then unable to climb back out.